Making S3 More Resilient Using Lambda Edge (opens in new tab)

I think it's still a reduction in risk overall. In the old model, they were vulnerable to S3 failing in one region, a thing that's happened many times. Now they've mitigated the S3-failure-in-one-region issue, at least mostly (though as you point out, how they do so is unknown), and in exchange they've picked up a dependency on Lambda@Edge. But Lambda@Edge, like CloudFront, is a global service distributed across many regions, and to my knowledge AWS has never had a global Lambda@Edge outage.

It's not impossible, of course. Some kind of control plane error could probably knock the whole global service offline. But I'd rather bet on a multi-region service than have all my eggs in one regional basket.

> Now they can add Lambda outages to that list too.

Specifically Lambda@Edge though, which changes the math a little.

That said, currently the better solution is CloudFront Origin Groups.

That's a relatively new feature (from November 2018... wow, has it been a year already?). My guess is that they implemented this stuff before that existed or maybe near to its release.

I have not used origin failover either, though I'm pretty sure you're right that this is its exact use-case.

I disagree.

A single region can go down (and has in the past), no matter how reliable S3 as a whole is. If your business wants to avoid downtime, this is a simple solution to further reduce risks that cause downtime.

Just because other sites might go down, doesn't mean you have to accept it for your own.

They have cross-region replication.

Those are also our biggest pain points together with slow deployments (cloudfront distributions can take 10-20 minutes to update, which is required to rollout a new version) and no support for lambda aliases. We forwarded that to our contacts at AWS, please also do that :-)

Disclaimer: I work at Contentful.

If you are already using Cloudflare that is correct, if you don’t that is an alternative.

Adding another vendor into your stack can often come with none engineering complexity (e.g. data protection forms, contractual requirements from customers another vendor you need to work with, etc.) so this is an alternative to stay in AWS when you already use it.

Disclaimer: I work at Contentful.